package class1;

public class A {
    private int a;
    A(){a=50;}
    int getA(){return a;}
}
class B extends A{
      //未定义构造函数
    B(){super();}

}
class  TesterDefault{
    public static void main(String[] args) {
        B x=new B();
        System.out.println("x.getA()="+x.getA());
    }
}